Guansong Ji Supervised by - uni-due.de

Control of Integrated Circuits through I2C-Bus using

USB interface and GUI in Matlab

Guansong Ji

Supervised by

Prof. Dr.-Ing. Klaus Solbach

Institute of Microwave and RF-Technology

University of Duisburg-Essen

2014-10-23 1

Outline

1. Motivation

2. System Overview

3. I2C Bus Communication Protocol

4. Arduino Platform

5. PCB Design

6. Matlab GUI

7. Test of Matlab GUI and ICs

8. Conclusion

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1. Motivation

• Power Amplifier Project for 7T MRI.

• ICs require digital data input for the control

• Functions of the ICs need to be tested on a demonstrator PCB.

• Matlab GUI needs to be designed and tested.

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2. System Overview

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PC (MATLAB GUI) MP Arduino PCBUSB I2C Bus

Integrated Circuits

• PCA9543A (Switch)

• P82B96 (Bus Buffer)

• MAX5115 (DAC)

• PCA9554A (Register)

• PCF8591T (ADC)

3. I2C Bus Communication ProtocolI2C Bus

• Inter-Integrated Circuit (I2C, Trademark)

• Two-Wire Interface (TWI, simpler than SPI)

• Two Signal Wires: Serial Data (SDA) and Serial Clock (SCL)

• Serial Communication (slower, cheaper and easier)

• Byte-oriented Transfer (8 bits)

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3. I2C Communication ProtocolAn Example of communication protocol

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Start Repeated

start

Acknowledge

bit

StopSCL Low

SDA Change

MSB

3. I2C Communication ProtocolAn example of Write Operation (MAX5115)

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• 7-bit slave address followed by one Read/Write bit.• High is Read, Low is Write.

• The Acknowledge bit is sent by the slave device.

• How are the command and data defined?

3. I2C Communication ProtocolAn example of Write Operation (MAX5115)

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3. I2C Communication ProtocolAn example of Write Operation (MAX5115)

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• For Write Operation,C7 and C6 should be 0.

• C5 and C4 are set toselect NV or V.

• C3-C0 are set to selectthe respective DACregister.

3. I2C Communication ProtocolAn example of Write Operation (MAX5115)

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Unipolar Code Output Voltage

4. Arduino Platform

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• Arduino Mega 2560

• Arduino IDE

(Integrated Development Environment)

• Support Package (by MathWorks)

4. Arduino PlatformMATLAB Support Package for Arduino

• adiosrv.pde

(Firmware uploaded to the Arduino Board)

• aduino.m

(Matlab class definition file, object-oriented)

• They have to be modified for the I2C Bus

(adiosrvDAC.pde and aduinoDAC.m)

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4. Arduino PlatformFirmware uploaded to Arduino Board

• Wire Library

• Function setup()• Serial.begin(115200);

• Function Loop()• If statement (Input)

• Switch statement

• Initial state s is set to be -1

• Cases (Process and Output)

• State Machine

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Initialization

Input

Process

Output

Initialization

Infinite

Loop

4. Arduino PlatformMatlab class definition file

• Object-oriented Programming Approach

• Classdef arduinoDAC < handle

• Class Properties and Class Methods

• The class defines an Arduino Object

• Functions used in the I2C Communications• checkI2Caddress (a, addr);

• i2cWriteCommand (a, address, command);

• i2cWriteData (a, address, command, data);

• i2cReadCommand (a, address, command);

• i2cReadData (a,address)

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5. PCB Design

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Finished Board Design of Software Eagle

5. PCB Design

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The assembly of PCB

PCA9543A

MAX5115 PCA9554APCF8591T

P82B

6. Matlab GUIMultiWindow GUI

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global ComPort

contents = cellstr(get(hObject,'String'));

ComPort = contents{get(hObject,'Value')};

clear a; % Clear the variable a

global a ComPort;

clc; % Clear Command Window

a = arduinoDAC(ComPort); %connect Matlab with the board and create an arduino object

6. Matlab GUIMultiWindow GUI

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PCA9543A MAX5115

6. Matlab GUIMultiWindow GUI

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PCA9554A

PCF8591T

6. Matlab GUI16 cassettes GUI

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Main Panel

6. Matlab GUI

16 cassetes GUI

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Control Panel

7. Test of Matlab GUI and ICs

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SDA

SCL

5V

GND

8. Conclusion

• PCB has been designed and soldered

• Two versions of Matlab GUI has been designed

• The Matlab GUI and ICs have been tested

• New version of Support Package for Arduino

• GUI could be more convenient

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Thank you for yourattention!

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